Air heating and potable water system having a water heater and a hydronic air handler

ABSTRACT

Air heating and potable water systems have a thermostat with a computer processing unit (CPU), a hot water heater, a hydronic air handler, and a primary pump controlling flow of hot water from the water heater into the hydronic air handler, which has a hydronic coil, a blower, and a first control panel having a CPU in operative communicates with the thermostat. The hydronic coil receives hot water from the water heater to warm air passing over the hydronic coil. The primary pump is in operative communication with the first control panel and an indicator of hot water flow. The indicator of hot water flow is in operative communication with either the thermostat or the first control panel, and any CPU in the system stores a priority instruction, which upon an indication of hot water flow deactivates or delays activation of the primary pump for a predetermined period of time.

RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.63/111,963, filed on Nov. 10, 2020, the entirety of which isincorporated herein by reference.

TECHNICAL FIELD

The invention relates to an air heating and potable water system, moreparticularly, an air heating and potable water system having a waterheater, which can be tankless, in fluid communication with a hydronicair handler, a sensor sensing flow in a building's hot water supply, anda thermostat in communication with the sensor and the hydronic airhandler to delay activation of the hydronic air handler during use ofhot water within the building.

BACKGROUND

In the heating and cooling industry, there are many ways ofheating/cooling air for domestic and commercial buildings. Thetraditional method is a furnace and air conditioning system. With theincrease in demand for “on-demand” tankless hot water heaters, there hasbeen recognition that the tankless hot water heater can also assist inheating air rather than requiring a traditional furnace. An air handlerin conjunction with the tankless hot water heater can serve thisfunction. The tankless water heater supplies hot water to the airhandler to generate heated air. Such a system must balance the demandfor heated air with the demand for heated water for use by sinks,dishwashers, showers, etc. There is a need for improvements in tanklesshot water heater-air handler systems regarding how the demand for theheated water is controlled.

For buildings utilizing an air handler-heat pump combination for heat,there is a significant electricity cost in running this combination inclimates that have a long cold season or a colder season based ontemperatures, such as in the north and northeastern parts of the U.S.and Canada. An air handler-heat pump combination does not include ahydronic coil. Rather, the air handler includes an electric heatingelement to generate heat when the heat pump is unable to meet thedemand. The electric heating element energizes when a sensor within theair handler reads a lower supply air temperature than the setpointdemand. The electric heating element compensates to raise the airtemperature to the setpoint demand. An electric heating element draws alarge amount of electricity and will greatly affect the electric billfor the building, i.e., making the bill higher. There is a need tomodify these air handler-heat pump combination systems to provide analternate air heating method to compensate for the heat pump when itcannot meet the setpoint demand that is more energy efficient.

SUMMARY

In all aspects, air heating and potable water systems for buildings aredescribed herein. These systems have a thermostat having a computerprocessing unit with nontransitory memory comprising a heatinginstruction, a hot water heater, a hydronic air handler having ahydronic coil, a blower, and a first control panel having a computerprocessing unit with nontransitory memory. The hot water heater has awater heater control panel having a computer processing unit withnontransitory memory. The first control panel is in operativecommunication with the thermostat, and the hydronic coil is in fluidcommunication with the hot water heater and receives hot water from thehot water heater to warm air passing over the hydronic coil. The systemalso has a primary pump controlling fluid communication of hot waterfrom the hot water heater to the hydronic coil and is in operativecommunication with the first control panel. The system has an indicatorof hot water supply usage within the building and in operativecommunication with either the thermostat or the first control panel.Either the computer processing unit of the thermostat, the first controlpanel, or the water heater control panel stores a priority instruction,which upon an indication of hot water flow to the hot water supply ofthe building from the sensor deactivates or delays activation of theprimary pump by a predetermined period of time. The priority instructionis configured to send a signal to the hot water heater to activate thehot water heater, which provides hot water to the hot water supply ofthe building while the primary pump is deactivated or delayed for thepredetermined period of time.

The hot water heater can be a tankless gas or electric hot water heater,a hydrogen eater splitting hot water heater, or a Peltier thermoelectrichot water heater.

In all aspects, the thermostat can be in direct electrical communicationor has a wireless communication with the control panel of the hydronicair handler. The primary pump can be external to the hydronic airhandler. The indicator of hot water supply usage within the building isa pressure sensor or a fluid flow sensor compatible with potable waterpositioned in the hot water supply of the building, is the hot waterheater control panel, or the thermostat. The sensor can be adifferential pressure sensor, which can be an absolute pressure sensoror a gauge pressure sensor. The predetermined period of time is selectedfrom the group consisting of 15 minutes, 20 minutes, 25, minutes, and 30minutes or is equivalent to the minutes for a cycle of an appliancewithin the building that uses hot water.

In all aspects, the first control panel or the thermostat stores a firstblower instruction in the computer processing unit thereof to continueactivation of the blower and primary pump for a post-heat period oftime; wherein, after a setpoint demand for heat has been reached, theblower instruction signals the blower and the primary pump to continueactivation thereof for the post-heat period of time to utilize residualheat stored in any of the components in the system. The first controlpanel or the thermostat stores a second blower instruction in thecomputer processing unit thereof to run the blower at a reduced ratewhen there is no call for air-conditioning or heating for a ventilationperiod of time.

The systems can further comprise a heat pump positioned exterior to thebuilding, an indicator of outdoor ambient air temperature, an evaporatorcoil within the interior of the building in fluid communication with acondenser of the heat pump and the evaporator coil is in fluidcommunication with the blower of the hydronic air handler for passingair over the evaporator coil. The heat pump includes the condenser, arefrigerant within the condenser, a compressor, a second control panelhaving a computer processing unit with nontransitory memory, and areversing valve. The thermostat is in operative communication with thesecond control panel and has a cooling instruction for activating theheat pump to provide air conditioning to the building. Either thecomputer processing unit of the thermostat, the first control panel, orthe second control panel stores a reversing instruction, which upon anindication of outdoor ambient air temperature being warmer than apredetermined set point temperature and a call for heat, activates thereversing valve of the heat pump to send heated refrigerant to theevaporator coil to heat air passing over the evaporator coil and thefirst control panel keeps the primary pump deactivated. The indicator ofambient air temperature is a temperature sensor at the exterior of thebuilding in operative communication with the thermostat or is atemperature algorithm stored in nontransitory memory of the thermostatthat is configured to monitor cycle times and operation times of theheat pump to simulate outdoor air temperature and calculate when theheat pump or the hydronic air handler acts as primary heat source. Thetemperature sensor is a sensor positioned to sense ambient airtemperature at the exterior of the building or is a digital source inelectrical communication with the thermostat.

In another aspect, a hydronic kit for an air handler-heat pump system ofa building with a hot water generating system is disclosed. The kitincludes a hydronic coil, a primary pump configured to be connected influid communication with the hydronic coil to pump hot water into thehydronic coil and in fluid communication with hot water from a hot watergenerating system, a control interface circuit having a computerprocessing unit with nontransitory memory connectable to a control panelof an air handler-heat pump system and configured to control activationof a blower of the air handler-heat pump system and configured toreceive an indication of hot water supply usage within the building, anda wiring harness configured to connect the primary pump and the hotwater generating system to the control panel of the air handler-heatpump system. The control interface circuit stores a priority instructionthat upon an receipt of an indication of hot water supply usage withinthe building, a deactivation or delay activation signal is sent to theprimary pump to deactivate or delay activation for a predeterminedperiod of time. In one embodiment, the deactivation or delay activationsignal is sent from a thermostat in the building to the primary pump.

In one embodiment, the indication of hot water supply usage is receivedfrom a sensor included in the kit that is positionable to determine flowof hot water in a hot water supply of a building and configured foroperative communication with the control interface circuit, thethermostat, and/or the control panel of the air handler-heat pumpsystem. In all aspects of the kit, the sensor is a pressure sensor or afluid flow sensor and is compatible with potable water, such as adifferential pressure sensor, which can be an absolute pressure sensoror a gauge pressure sensor. The predetermined period of time is selectedfrom the group consisting of 15 minutes, 20 minutes, 25, minutes, and 30minutes or is equivalent to the minutes for a cycle of an appliancewithin the building that uses hot water. The control interface circuitis configured for switching between hydronic heating-heat pump mode andair handler-heat pump mode.

In all aspects, the kit can further include an indicator of outdoorambient air temperature. The control interface circuit stores areversing instruction, upon an indication of outdoor ambient airtemperature being warmer than a predetermined set point temperature anda call for heat, configured to activate a reversing valve of the heatpump to send heated refrigerant to the evaporator coil to heat airpassing over the evaporator coil and the control interface circuit keepsthe primary pump deactivated. The indicator of ambient air temperatureis a temperature sensor at the exterior of the building in operativecommunication with the thermostat, is a digital source in electricalcommunication with the thermostat or the control circuit interface, oris a temperature algorithm stored in nontransitory memory of thethermostat that is configured to monitor cycle times and operation timesof the heat pump to simulate outdoor air temperature and calculate whenthe heat pump or the hydronic air handler acts as primary heat source.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic of an air heating and potable water system.

FIG. 2 is one example of the duct work connection to the hydronic airhandler unit of the system of FIG. 1.

FIG. 3 is a front perspective view of a hydronic air handler with itsfront cover removed.

FIG. 4 is an exploded view of the hydronic air handler of FIG. 3.

FIG. 5 is an exterior building view of the heat pump unit in FIG. 1.

FIG. 6 is a side perspective view of a heat pump with its front and topremoved.

FIG. 7 is a partial exploded view of the heat pump unit in FIG. 6.

FIG. 8 is a schematic representation of the communication between theheat pump and the evaporator coil.

FIG. 9 is a schematic of an air handler-heat pump heating systemretrofitted to have a hydronic kit to heat the building in the colderseason.

DETAILED DESCRIPTION

The following detailed description will illustrate the generalprinciples of the invention, examples of which are additionallyillustrated in the accompanying drawings. In the drawings, likereference numbers indicate identical or functionally similar elements.

Referring to FIG. 1, an air heating and potable water system of abuilding, referred to by the reference 100, is shown schematically toinclude a thermostat 102, a tankless hot water heater 104, a hydronicair handler 106, an evaporator coil 108 (shown as an A-coil), a heatpump 110, and a primary pump 112. The system of FIGS. 1-3 is an openheat transfer system because the water in the system is constantlychanging as the potable water is used for other household or buildinguses, such as toilets, sinks, showers, baths, or by dish washers,washing machines, etc. The heat pump 110 is positioned exterior to awall 114 of the building and the other units are in the interior of thebuilding. The tankless hot water heater 104 has a gas supply line (G) influid communication with a gas inlet 118 in FIG. 1, but is not limitedthereto as the means to heat the water. In other embodiments, thetankless hot water heater could be an electrical unit or an alternateenergy source such as hydrogen or photo voltaic. The tankless hot waterheater can be any commercially available unit or hereinafter developedunit. The tankless hot water heater 104 has a water inlet 120 receivingthe water supply and a water outlet 122 for the heated water. Each ofthese inlets and outlets can have universal fittings for installationand replacement purposes. Further, each conduit/piping leading therefromcan include a manual shot off valve 124 and/or a manual drain 126. Thetankless hot water heater can include a condensate drain line if needed.The tankless hot water heater 104 has its water outlet 122 in fluidcommunication with the building hot water supply 130, which can includea mixing valve 128 receiving cold water, and in fluid communication withthe primary pump 112 that pumps hot water into the hydronic air handler106. The system can include check valves 142 positioned as needed, suchas in the cold water supply and the water return from the hydronic airhandler shown in FIG. 1.

While a tankless hot water heater is illustrated in FIG. 1, inparticular, a tankless gas hot water heater, the invention is notlimited thereto. In one embodiment, the hot water heater can be anelectric tankless hot water heater. In another embodiment, the hot waterheater can be a Peltier element hot water heater. In yet anotherembodiment, the hot water heater can be a carbon zero hot water heater,i.e., any commercially available or herein after developed electric hotwater heater. One specific example of a carbon zero hot water heater isa HYDRO ZERO™ tankless hot water heater, which utilizes the energy fromsplitting water into hydrogen and oxygen in a plasma state, made byHydro Zero of Union Bridge Works, Roker Lane, Pudsey, Leeds, LS28 9LEand available in North America from Carbon Zero Solutions, Ltd. ofVancouver, BC, Canada.

The system can include an expansion tank 144. In FIG. 1, the expansiontank 144 is in fluid communication with the cold water supply. Turningnow to FIG. 2, the housing 109 for the evaporator coil 108 is seated ontop of the hydronic air handler 106 and is in fluid communication withthe blower of the hydronic air handler for the passage of air over andthrough the evaporator coil. In fluid communication with and above thehousing 109 of the evaporator coil 108 is a duct branch 146 having aplurality of dampers 148 controlling air flow through the ducts 150leading to different rooms or spaces with the building. Also shown inFIG. 2 is the air return duct 152 returning air to the blower section ofthe hydronic air handler 106.

The primary pump 112 controls the fluid communication of the hot waterfrom the tankless hot water heater 102 into the hydronic air handler106. In FIGS. 1 and 2, the primary pump 112 is positioned external tobut most proximate the hydronic air handler 106. However, as representedby the dashed box 140 within the hydronic air handler 106, the primarypump may be within the interior of the housing of the hydronic airhandler.

The system 100 includes a sensor 132, also referred to herein as apriority switch, positioned to determine flow of hot water into thebuilding's hot water supply 130. The sensor or priority switch 132 canbe any suitable sensor that is compatible and safe for use with hotpotable water. The sensor 132 can be a pressure sensor or a fluid flowsensor. If a pressure sensor is selected, the sensor can be an absolutepressure sensor, a differential pressure sensor, or a gauge pressuresensor. In one embodiment, the pressure sensor is a differentialpressure sensor. The sensor 132 is in operative communication with thethermostat 102, first control panel 116 of the hydronic air handler 106,and/or the third control panel 136 of the tankless hot water heater 104.

The thermostat 102 is in operative communication with (i) the hydronicair handler 106, more particularly with a first control panel 116thereof, and/or (ii) the heat pump 110, more particularly with a secondcontrol panel 134 thereof, and optionally with (iii) the sensor 132. Thefirst control panel 116 of the hydronic air handler 106 is in operativecommunication with the thermostat 102, the primary pump 112, the secondcontrol panel 134 of the heat pump 110, and optionally with the sensor132 and optionally with a third control panel 136 of the tankless hotwater heater 104. The operative communications within the system 100(represented by the dashed lines in FIG. 1) can be electrical or othertypes of wired direct communications or may be any type of wirelesscommunications. Each control panel includes a computer processing unitwith a nontransitory medium to store instructions, algorithms, and thelike.

The thermostat 102 has a display 103, which can be a touch screendisplay, an onboard computer processing unit housed within its housing,and nontransitory memory, i.e., computer readable media, in which isstored a heating instruction, a cooling instruction, algorithms, andoptionally, a priority instruction and a reversing instruction. Theheating instruction is activated when the thermostat 102 receives ademand for space heating. The heating instruction causes the thermostat102 to signal the first control panel 116 for operation of the hydronicair handler 106. More particularly, the thermostat 102 signals the firstcontrol panel 116 to activate the primary pump 112 to circulate waterfrom the tankless hot water heater 104 to the hydronic air handler 106and, when the tankless hot water heater senses water flow as a result ofthe primary pump's activation, the tankless hot water heater begins toheat water to meet the setpoint demand from the thermostat 102. When theheating setpoint demand is achieved, the thermostat 102 signals thefirst control panel 116 to deactivate the primary pump 112, which causesthe tankless water heater 104 to sense an absence of water flow, therebydeactivating the tankless hot water heater.

When there is a demand for hot water for use within the building, thesensor 132 (priority switch) detects a drop in static pressure withinthe hot water supply piping. Depending upon how the system isconfigured, the sensor or priority switch 132 can send its measurementdata or signal to either the thermostat 102 or the first control panel116. Whichever receives the signal from the sensor 132 will have storedtherein, in its nontransitory memory, a priority instruction. Thepriority instruction is, upon receipt of an indication of use of hotwater in the building from the sensor or priority switch 132, to signalthe third control panel 136 from the first control panel 116 toenergize/activate the tankless hot water heater 102 and provide hotwater to the plumbing fixtures, dishwashers, etc. that are in demandthereof and to deactivate or delay activation of the primary pump 112for a preselected period of time.

The reversing instruction may be stored in the computer processing unitof the thermostat 102, the first control panel 116, or the secondcontrol panel 134. The reversing instruction is for operation of theheat pump in reverse to heat air in the spring and fall when exteriorambient temperatures are suitable, rather than activate the primary pump112 and the tankless hot water heater 102. The reversing instruction,upon an indication from the temperature sensor of ambient airtemperature being warmer than a predetermined set point temperature anda call for heat, activates the reversing valve of the heat pump to sendheated refrigerant to the evaporator coil 108 to heat air passing overthe evaporator coil and the first control panel keeps the primary pumpoff.

Referring now to FIGS. 3 and 4, the hydronic air handler 106 has ahydronic coil 202 positioned above a blower 204, which can be mounted atan angle relative to a chute outlet 207 of a chute 206 directing airflow from the blower 204 into direct contact with and through thehydronic coil 202 and out a primary outlet 209 of the hydronic airhandler 106. The section of the housing 200 enclosing the blower 204 mayinclude a sound attenuating material 210 positioned to reduce soundnoise generated by the blower during operation of the unit, and optionalknockout access panels 220 for connection to an air return duct. Theblower 202 has a motor 212 operating a fan that directs air through thechute 206 toward the hydronic coil 202. The hydronic coil 202 has a hotwater inlet 214 in fluid communication with the primary pump 112(FIG. 1) and receives hot water from the tankless hot water heater 104to warm air passing over the hydronic coil 202 and has a water outlet216 in fluid communication with the tankless hot water heater 104 tosend water back thereto to be heated again.

As best seen in FIG. 3, the hydronic air handler 106 has a terminal 222which is a mounting surface for onboard terminals 244 and 226 and has aslot 223 for an optional interface card 225, which are all in electricalcommunication with the first control panel 116. The onboard terminal 224is configured for plug-and-play electrical connections to the thermostat102, the building's power source, the primary pump (power andcommunication), and a ground wire. The optional slot 223 for aninterface card is for a card programmed to interface with any of theother units in the system, such as the tankless hot water heater, thesensor, or the heat pump. The terminal for the thermostat may be a 24Vterminal 224 and the building's power may require 120V terminal 226. Thehousing 200 can include knockout access openings 228 for wires to reachthe terminals 224, 226.

In the exploded view of FIG. 4, the housing 200 includes a bottom panel230, a partition panel 232 separating the blower 204 from the hydroniccoil 202, except for the chute outlet 207 defined thereby, and a toppanel 234 defining the primary outlet 209 and having openings thatreceive the inlet and the outlet of the hydronic coil. Each of thesepanels 230, 232, and 234 are oriented horizontally (parallel to theground). A front panel 238 is present and includes a handle 240 and anindicator 242. Additionally, a connection frame 244 for connection tothe air return duct can be positioned against a selected knockout accesspanel.

The first control panel 116 or other computer processing unit 102, 136in the system has a first instruction stored in its nontransitory memoryto deactivate or delay activation of the primary pump 112 by apredetermined period of time when the thermostat 102 sends a call forheat to the first control panel 116 and the first control panel 116 hasan indication of hot water flow to the hot water supply of the building.The indication of hot water flow to the building may come from sensor132, the third control panel 136 of the tankless hot water heater 104,or the thermostat 102, any of which may directly indicate or have acomputer processing unit that can be programmed to indicate hot wateruse within the building. The predetermined time period can be 15minutes, 20 minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, orthe typical number of minutes for the dishwasher, washing machine, etc.of the building, which ever has the longest cycle. In the system of FIG.1, a demand call from the thermostat 102 signals the hydronic airhandler 106, which turns on the primary pump 112 and then the blower204. When the primary pump 112 turns on, a switch therein signals thetankless water heater 102 to heat the water. In this system, the primarypump 112 is not turned on in response to a call for heat when the sensor132 senses hot water use, the third control panel 136 of the tanklesshot water heater 104 indicates hot water use, or the thermostat 102indicates hot water use within the building. Rather, after thepredetermined period of time has passed, the first control panel 116will signal the primary pump 112 to turn on and will instruct thetankless hot water heater to produce hot water. The primary pump 112will be “on” at normal operating gallons per minute until the thermostatachieves a setpoint and the call for heat has been satisfied.

When the setpoint demand from thermostat 102 is achieved the firstcontrol panel 116 sends a signal to tankless hot water heater 104 tode-energize, and, in accordance with a first blower instruction, theblower motor 204 and the primary pump 112 will continue to operate for aset period of time determined by control panel 116 or the thermostat 102to circulate water through hydronic coil 202. The first blowerinstruction is stored in the computer processing unit of either thethermostat 102 or the first control panel 116. This extended run time ofthe blower motor and primary pump scrubs off residual heat stored in thewater piping between water heater 104 and air handler 106 and thehydronic coil 202 and the heat exchanger in the tankless hot waterheater 104. This increases the overall efficiency of the space heating.

During the time when there is not a call for air-conditioning orheating, either from the heat pump 110 or the tankless hot water heater104, the blower motor 204 in the air handler 106 can continue to operateat reduced cubic feet per minute (CFM) or part loads based on anadditional instruction, a second blower instruction, stored in thenontransitory memory of the CPU of the first control panel 116 or thethermostat 102. This provides air flow throughout the building for aventilation period of time, thereby meeting various ventilationrequirements. In one embodiment, the ventilation period of time istwenty four hours, seven days a week. In other embodiments, theventilation period of time less than twenty four hours at period timeswithin a twenty four hour period.

The first control panel 116 can have a refresh instruction stored in thecomputer processing unit as well. The refresh instruction is configuredto activate the primary pump 112 at preselected intervals within each 24hour period to circulate water within the water piping and the hydroniccoil 202 to prevent stagnation of water within the system. Thepreselected interval may be any number of hours within the range of 4 to12 hours, thereby refreshing the system up to six times, 4 times, or 2times in a 24 hour period.

Turning now to FIG. 5-7, the heat pump 110 is shown in more detail,which as noted with respect to FIG. 1 is exterior to the wall(s) 114 ofthe building. With reference to FIG. 5, the heat pump 110 has a housing300 that includes a front grill 302, a top cover 304 and a valve cover306. Protruding from the valve cover 306 are the supply conduit 308 andthe return conduit 310. With reference to FIG. 6, the housing includes afront cabinet plate 312 defining a circular opening for the fan 314 todraw air across a condenser 320 (FIG. 7), right side plate 315, leftside plate 317, base 319, and clapboard 313 separating the fancompartment form the compressor compartment. The fan 314 is operated bymotor 315 (FIG. 7) that is held in place in the housing by the motorsupport sub-assembly 326. Seated below the top cover 304 is a firstelectrical box 316 and a second electrical box 318 housing variouselectronic components for the operation of the heat pump 110. A secondcontrol panel 134 (FIG. 1) is housed inside the second electrical box318.

As shown in FIG. 7, the heat pump 110 has a condenser 320 filled with arefrigerant, a compressor 322 to operatively move the refrigerantthrough the system, an electric heater 323, and a reversing valve 324 influid communication with the compressor and the condenser to control theflow of the refrigerant from the condenser 320 to the evaporator coil108 within the building. The condenser 320 is protected from damage fromthe exterior environment by a rear grill 328. The heat pump 110 alsoincludes a valve support plate 330 supporting a two-way valve 332 on theliquid side of the heat pump and a three-way valve 334 on thegas/suction side of the heat pump. The heat pump 110 typically is usedto provide air conditioning (cooling) in the summer months and springand fall when temperatures require cooling of the space within thebuilding and the thermostat 102 executes the cooling instruction andsends a demand for cooling to the first control panel 116 and/or thesecond control panel 134. The cooling instruction sends an activationsignal to the second control panel 134 either directly or through thefirst control panel 116 to activate the heat pump in its normal mode,which sends cold refrigerant to the evaporator coil 108 within thebuilding and sends an activation signal to the first control panel 116to turn on the blower 204 of the hydronic air handler 106. When thecooling setpoint demand is achieved, the thermostat 102 signals thefirst control panel 116 or the second control panel 134 to deactivatethe heat pump 110 and signals the first control panel 116 tosubsequently (after a predetermined period of time) or simultaneously todeactivate the blower 204.

Returning to FIG. 1, the system of also includes a temperature sensor150 for determining ambient air temperature at the exterior of thebuilding. The temperature sensor 150 can be an actual sensor positionedat the exterior of the building proximate the heat pump or one builtinto the heat pump to sense the ambient air temperature at the exteriorof the building. In another embodiment, the temperature sensor 150 isfrom a digital source connected to the thermostat over the internet orany other electronic communication format know or herein afterdeveloped, e.g., a local weather station, local weather web page, etc.,i.e., it is not physically located proximate the heat pump or thebuilding but still communications the ambient air temperature relativeto the building.

The thermostat 102 is in operative communication with the second controlpanel 134 of the heat pump, either directly or through the first controlpanel 116 of the hydronic air handler 106. The thermostat 102 has asecond instruction that utilizes the ambient air temperature from thetemperature source 150 compared to a predetermined setpoint temperatureto determine, when based on a call for heat, to leave the primary pump112 off and to activate the reversing valve 324 of the heat pump 110 tosend heated refrigerant to the evaporator coil 108 to heat air passingover the evaporator coil 108 using the blower 204 of the hydronic airhandler 106. Since heat pumps lose efficiency during the colder monthsthe thermostat 102 has an algorithm stored in its nontransitory memorythat is executable by the onboard computer processing unit. Thealgorithm instructs the thermostat to only run heat pump in reverseduring the “should seasons,” basically spring and fall, when theefficiencies are best for extracting heat from the ambient exterior air.When ambient exterior temperature falls below the predeterminedsetpoint, the system automatically switches to the on demand tanklesshot water heater 102 to provide hot water to the hydronic coil 202 inthe hydronic air handler 106 and activates the primary pump 112 asdescribed above. Optionally, instead of an outdoor temperature sensor150, the thermostat 102 may have a preprogrammed algorithm within thenontransitory memory which monitors cycle times and operation time ofthe heat pump to simulate outdoor air temperature and calculate the besttime (balance point) to cycle between the heat pump for primary heat orthe hydronic air handler as the primary heat source. Energy modelingshows a significant reduction in carbon emissions when using the heatpump during spring and fall heating cycles. This system may be referredto as “eco-friendly.”

Referring now to FIG. 9, in another aspect, we disclose a hydronic kit460 for converting existing air handler-heat pump heating systems 400for a building 114 with a hot water generating system 405, such as a hotwater tank or tankless unit, to function as described above. Thehydronic kit 460 has a hydronic coil 462, a primary pump 464, a controlinterface circuit 466, a wiring harness 468, and optionally, a sensor469. The air handler is reference 407 and the heat pump is reference410. The primary pump 464 is configured to be connected in fluidcommunication with the hydronic coil 462 and in fluid communication withhot water from a hot water generating system 405. The primary pump 464is configured to pump hot water into the hydronic coil 462 when warm airis demanded by a thermoset 402. The control interface circuit 466 has acomputer processing unit 467 with nontransitory memory connectable to acontrol panel 416 of an air handler-heat pump system 400 and isconfigured to control activation of a blower (not shown) within the airhandler 407 of system 400. The sensor 469 is positionable downstream ofa cold-hot water mixing valve 428 to determine flow of hot water in thehot water supply of the building and is configured for operativecommunication with the control interface circuit 466 and/or the controlpanel 416 of the air handler-heat pump system 400. The wiring harness468 is configured to connect the primary pump 464 and the hot watergenerating system 405 to the control panel 416 of the air handler-heatpump system 400. The control interface circuit 466 stores a priorityinstruction that upon an indication from the sensor 469 of hot waterflow in the hot water supply of the building, a deactivation or delayactivation signal is sent to the primary pump 464 to deactivate or delayactivation for a predetermined period of time as described above.

In FIG. 9, normal operation, without the hydronic kit 460 option, thethermostat 402 sends a signal to the control panel 416 in the airhandler 407 that the setpoint demand has been achieved, the controlpanel 416 then deenergizes the blower of the air handler 407 anddeenergize the supplemental heating element 409 in the air handler 407if it is in operation. Since there are many brands of air handler-heatpump systems on the market it would be difficult to design a controlinterface circuit 466 for each control panel 416 for the various brands.It is preferable to use the control signal from the thermostat 402 asthe mechanism to activate the pump 464 in the hydronic kit 460, tointerface with the control panel 416 to control the blower of the airhandler 407, and to activate/deactivate the supplemental heating element409 in the various air handlers available.

In operation, when the hydronic kit is installed instead of thesupplemental heating element 409 in the air handler 407, the signal fromthe thermostat 402 that would normally be connected directly to the airhandler 407 by low voltage wiring is interrupted by the controlinterface circuit 466. The computer processing unit 467 of the controlinterface circuit 466 is configured to modify the signal from thethermostat 402. During a call for heat from the thermostat 402, thethermostat 402 sends a signal to the control panel 416, the signal isthen modified by the computer processing unit 467 of the controlinterface circuit 466 and the modified signal activates the primary pump464. For example, a 110V/24V relay within the control interface circuit466 activates the 110V pump 464. The control interface circuit 466 thencompletes the electrical circuit, thereby allowing the signal from thethermostat 402 to activate the blower thru control panel 416 of the airhandler 407. The control panel 416 will then operate the air handler 407and heat pump 410 as normally programmed from the factory whether inheating or cooling mode as dictated by the thermostat 402. Theevaporator coil 408 will still provide heat from the heat pump 410 inaddition to the heat provided by the hydronic kit 460 reaching thedesired setpoint demand from the thermostat 402 in the sameconfiguration as if the electric heating element had been used. Thecomputer processing unit 467 in the control interface circuit 466 can beprogrammed with the same instructions described above for the embodimentof FIG. 1, except for the blower control which is controlled by the airhandler's control panel 416.

One of the instructions, is a reversing instruction that, upon anindication from the temperature sensor 450 of ambient air temperaturebeing warmer than a predetermined set point temperature and there beinga call for heat, activates a reversing valve 435 of the heat pump 410, afactory component therein, to send heated refrigerant to the evaporatorcoil 408 to heat air passing over the evaporator coil and signals thecontrol interface circuit 466 to keep the primary pump 464 deactivated.

In one embodiment, the control interface circuit 466 is configured forswitching between hydronic heating-heat pump mode and air handler-heatpump mode. In one embodiment, a mode selector dip switch is present toselected either the hydronic heating-heat pump mode or the airhandler-heat pump mode. The air handler-heat pump mode will use anelectric heating element to supplement the heat pump when the heat pumpcannot meet the heat demand in its standard factory mode of heating/airconditioning, which will be less efficient than the hydronicheating-heat pump mode for heating the building.

Still referring to FIG. 9, the hydronic kit 460 can include atemperature sensor 450 configured for operative communication with thecontrol interface circuit 466. The temperature sensor 450 can bemountable at a position exterior to the building 114 to sense ambientair temperature generally proximate the heat pump 410. In anotherembodiment, the temperature sensor 450 is a digital source in electricalcommunication with the control circuit interface 466. Possible examplesof the digital source are provided above with respect to the discussionof FIG. 1. Optionally, instead of an outdoor temperature sensor 450, thethermostat 402 may have a preprogrammed algorithm within thenontransitory memory, which monitors cycle times and operation time ofthe heat pump to simulate outdoor air temperature and calculate the besttime (balance point) to cycle between the heat pump for primary heat orthe hydronic air handler as the primary heat source.

Besides more efficient, economical heating using the hydronic kit, thebuilding owner may be able to benefit from gas and electric utilityrebates for installing a unit that reduces the carbon footprint. In somejurisdictions, there may be a rebate from the electric utility for theinstallation of an air handler-heat pump system. When this system ismodified by the installation of the hydronic kit, the owner of thebuilding may qualify for a rebate from the gas utility as well.

In British Columbia, Canada, the Energy Step Code measures a building'senergy performance by a variety of metrics. The Building EnvelopeMetrics and the Equipment and Systems Metrics are demonstrated through awhole-building performance simulation. For the Building EnvelopeMetrics, thermal energy demand intensity is the amount of annual heatingenergy needed to maintain a stable interior temperature, taking intoaccount heat loss through the envelope and passive gains (i.e., theamount of heat gained from solar energy passing through the envelope, orfrom activities in the home such as cooking and lighting, and thatprovided by body heat). It is calculated per unit of area of theconditioned space over the course of a year and expressed inkWh/(m²·year). For Equipment and Systems Metrics, the first metric is“Percent Lower than EnerGuide Reference House.” This establishes howmuch energy a home would use if it was built to base building codestandards. This metric identifies how much less energy, stated as apercentage, the new home will require compared to the reference house.The second metric is “Mechanical Energy Use Intensity.” This metricmodels the amount of energy used by space heating and cooling,ventilation, and domestic hot water systems, per unit of area, over thecourse of a year, expressed in kWh/(m²·year). The third metric is “TotalEnergy Use Intensity.” This third metric models the amount of totalenergy use by a building per unit area, over the course of a year,expressed in kWh/(m²·year).

The hybrid systems disclosed herein, with the hydronic air handler, meetthe second metric of the Mechanical Energy Use Intensity. This is saidto achieve an Energy Step Code rating of 4 out of 5, which is a highrating exceeding existing space heating and cooling units. The hydronicair handler, a high efficiency tankless hot water heating unit to heathot water, and a heat pup operating in the shoulder season collectivelyuse less energy per unit area.

Although the invention is shown and described with respect to certainembodiments, it is obvious that modifications will occur to thoseskilled in the art upon reading and understanding the specification, andthe present invention includes all such modifications.

What is claimed is:
 1. An air heating and potable water system of abuilding comprising: a thermostat having a computer processing unit withnontransitory memory comprising a heating instruction; a hot waterheater having a water heater control panel having a computer processingunit; a hydronic air handler having a hydronic coil, a blower, and afirst control panel having a computer processing unit with nontransitorymemory, wherein the first control panel is in operative communicationwith the thermostat, and the hydronic coil is in fluid communicationwith the hot water heater and receives hot water from the hot waterheater to warm air passing over the hydronic coil; a primary pumpcontrolling the fluid communication of the hot water from the hot waterheater into the hydronic coil, the primary pump being in operativecommunication with the first control panel; and a indicator of hot watersupply usage within the building and in operative communication witheither the thermostat or the first control panel; wherein either thecomputer processing unit of the thermostat, the first control panel, orthe water heater control panel stores a priority instruction; wherein,the priority instruction upon an indication of hot water flow to the hotwater supply of the building directly from the sensor deactivates ordelays activation of the primary pump by a predetermined period of time.2. The system of claim 1, wherein the priority instruction is configuredto send a signal to the hot water heater to activate the hot waterheater, which provides hot water to the hot water supply of the buildingwhile the primary pump is deactivated or delayed for the predeterminedperiod of time.
 3. The system of claim 1, wherein the hot water heateris a tankless gas or electric hot water heater, a hydrogen eatersplitting hot water heater, or a Peltier thermoelectric hot waterheater.
 4. The system of claim 1, wherein the thermostat is in directelectrical communication or has a wireless communication with thecontrol panel of the hydronic air handler and the sensor.
 5. The systemof claim 1, wherein the primary pump is external to the hydronic airhandler.
 6. The system of claim 1, wherein the indicator of hot watersupply usage within the building is a pressure sensor or a fluid flowsensor compatible with potable water positioned in the hot water supplyof the building, is the hot water heater control panel, or thethermostat.
 7. The system of claim 1, wherein the predetermined periodof time is selected from the group consisting of 15 minutes, 20 minutes,25, minutes, and 30 minutes.
 8. The system of claim 1, wherein thepredetermined period of time is equivalent to the minutes for a cycle ofan appliance within the building that uses hot water.
 9. The system ofclaim 1, wherein, the first control panel or the thermostat stores afirst blower instruction in the computer processing unit thereof tocontinue activation of the blower and primary pump for a post-heatperiod of time; wherein, after a setpoint demand for heat has beenreached, the blower instruction signals the blower and the primary pumpto continue activation thereof for the post-heat period of time toutilize residual heat stored in any of the components in the system. 10.The system of claim 9, wherein the first control panel or the thermostatstores a second blower instruction in the computer processing unitthereof to run the blower at a reduced rate when there is no call forair-conditioning or heating for a ventilation period of time.
 11. Thesystem of claim 1, comprising: a heat pump positioned exterior to thebuilding, the heat pump comprising a condenser, a refrigerant within thecondenser, a compressor, a second control panel having a computerprocessing unit with nontransitory memory, and a reversing valve; anindicator of outdoor ambient air temperature; an evaporator coil withinthe interior of the building is in fluid communication with thecondenser of the heat pump and the evaporator coil is in fluidcommunication with the blower of the hydronic air handler for passingair over the evaporator coil; wherein the thermostat is in operativecommunication with the second control panel and has a coolinginstruction for activating the heat pump to provide air conditioning tothe building; wherein either the computer processing unit of thethermostat, the first control panel, or the second control panel storesa reversing instruction; wherein, the reversing instruction, upon anindication of outdoor ambient air temperature being warmer than apredetermined set point temperature and a call for heat, activates thereversing valve of the heat pump to send heated refrigerant to theevaporator coil to heat air passing over the evaporator coil and thefirst control panel keeps the primary pump deactivated.
 12. The systemof claim 11, wherein the indicator of ambient air temperature is atemperature sensor at the exterior of the building in operativecommunication with the thermostat or is a temperature algorithm storedin nontransitory memory of the thermostat that is configured to monitorcycle times and operation times of the heat pump to simulate outdoor airtemperature and calculate when the heat pump or the hydronic air handleracts as primary heat source.
 13. The system of claim 11, wherein thetemperature sensor is a sensor positioned to sense ambient airtemperature at the exterior of the building or is a digital source inelectrical communication to the thermostat.
 14. A hydronic kit for anair handler-heat pump system in a building with a hot water generatingsystem comprising: a hydronic coil; a primary pump configured to beconnected in fluid communication with the hydronic coil to pump hotwater into the hydronic coil and in fluid communication with hot waterfrom a hot water generating system; a control interface circuit having acomputer processing unit with nontransitory memory connectable to acontrol panel of an air handler-heat pump system and configured tocontrol activation of a blower of the air handler-heat pump system andconfigured to receive an indication of hot water supply usage within thebuilding; a wiring harness configured to connect the primary pump andthe hot water generating system to the control panel of the airhandler-heat pump system; wherein the control interface circuit stores apriority instruction that upon receipt of an indication of hot watersupply usage within the building, a deactivation or delay activationsignal is sent to the primary pump to deactivate or delay activation fora predetermined period of time.
 15. The hydronic kit of claim 14,wherein the deactivation or delay activation signal is sent from athermostat in the building to the primary pump.
 16. The hydronic kit ofclaim 15, further comprising a sensor positionable to determine flow ofhot water in a hot water supply of a building and configured foroperative communication with the control interface circuit, thethermostat, and/or the control panel of the air handler-heat pumpsystem.
 17. The hydronic kit of claim 16, wherein the sensor is apressure sensor or a fluid flow sensor and is compatible with potablewater.
 18. The hydronic kit of claim 14, wherein the predeterminedperiod of time is selected from the group consisting of 15 minutes, 20minutes, 25, minutes, and 30 minutes.
 19. The hydronic kit of claim 14,wherein the control interface circuit is configured for switchingbetween hydronic heating-heat pump mode and air handler-heat pump mode.20. The hydronic kit of claim 15, further comprising: an indicator ofoutdoor ambient air temperature; wherein the control interface circuitstores a reversing instruction, which, upon an indication of outdoorambient air temperature being warmer than a predetermined set pointtemperature and a call for heat, is configured to activate a reversingvalve of the heat pump to send heated refrigerant to the evaporator coilto heat air passing over the evaporator coil while the control interfacecircuit keeps the primary pump deactivated.
 21. The system of claim 20,wherein the indicator of ambient air temperature is a temperature sensorat the exterior of the building in operative communication with thethermostat, is a digital source in electrical communication with thethermostat or the control circuit interface, or is a temperaturealgorithm stored in nontransitory memory of the thermostat that isconfigured to monitor cycle times and operation times of the heat pumpto simulate outdoor air temperature and calculate when the heat pump orthe hydronic air handler acts as primary heat source.